4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
27 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2012, 2013, Intel Corporation.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
37 * This file is part of Lustre, http://www.lustre.org/
38 * Lustre is a trademark of Sun Microsystems, Inc.
40 * Internal interfaces of OSC layer.
42 * Author: Nikita Danilov <nikita.danilov@sun.com>
43 * Author: Jinshan Xiong <jinshan.xiong@whamcloud.com>
46 #ifndef OSC_CL_INTERNAL_H
47 #define OSC_CL_INTERNAL_H
50 # include <libcfs/libcfs.h>
52 # include <liblustre.h>
56 /* osc_build_res_name() */
58 #include <cl_object.h>
60 #include "osc_internal.h"
69 * State maintained by osc layer for each IO context.
73 struct cl_io_slice oi_cl;
74 /** true if this io is lockless. */
76 /** active extents, we know how many bytes is going to be written,
77 * so having an active extent will prevent it from being fragmented */
78 struct osc_extent *oi_active;
79 /** partially truncated extent, we need to hold this extent to prevent
80 * page writeback from happening. */
81 struct osc_extent *oi_trunc;
85 struct obd_info oi_info;
87 struct osc_async_cbargs {
90 struct completion opc_sync;
95 * State of transfer for osc.
98 struct cl_req_slice or_cl;
102 * State maintained by osc layer for the duration of a system call.
108 #define OTI_PVEC_SIZE 256
109 struct osc_thread_info {
110 struct ldlm_res_id oti_resname;
111 ldlm_policy_data_t oti_policy;
112 struct cl_lock_descr oti_descr;
113 struct cl_attr oti_attr;
114 struct lustre_handle oti_handle;
115 struct cl_page_list oti_plist;
117 struct cl_page *oti_pvec[OTI_PVEC_SIZE];
121 struct cl_object oo_cl;
122 struct lov_oinfo *oo_oinfo;
124 * True if locking against this stripe got -EUSERS.
127 cfs_time_t oo_contention_time;
128 #ifdef CONFIG_LUSTRE_DEBUG_EXPENSIVE_CHECK
130 * IO context used for invariant checks in osc_lock_has_pages().
132 struct cl_io oo_debug_io;
133 /** Serialization object for osc_object::oo_debug_io. */
134 struct mutex oo_debug_mutex;
137 * List of pages in transfer.
139 cfs_list_t oo_inflight[CRT_NR];
141 * Lock, protecting ccc_object::cob_inflight, because a seat-belt is
142 * locked during take-off and landing.
144 spinlock_t oo_seatbelt;
147 * used by the osc to keep track of what objects to build into rpcs.
148 * Protected by client_obd->cli_loi_list_lock.
150 cfs_list_t oo_ready_item;
151 cfs_list_t oo_hp_ready_item;
152 cfs_list_t oo_write_item;
153 cfs_list_t oo_read_item;
156 * extent is a red black tree to manage (async) dirty pages.
158 struct rb_root oo_root;
160 * Manage write(dirty) extents.
162 cfs_list_t oo_hp_exts; /* list of hp extents */
163 cfs_list_t oo_urgent_exts; /* list of writeback extents */
164 cfs_list_t oo_rpc_exts;
166 cfs_list_t oo_reading_exts;
168 cfs_atomic_t oo_nr_reads;
169 cfs_atomic_t oo_nr_writes;
171 /** Protect extent tree. Will be used to protect
172 * oo_{read|write}_pages soon. */
176 static inline void osc_object_lock(struct osc_object *obj)
178 spin_lock(&obj->oo_lock);
181 static inline int osc_object_trylock(struct osc_object *obj)
183 return spin_trylock(&obj->oo_lock);
186 static inline void osc_object_unlock(struct osc_object *obj)
188 spin_unlock(&obj->oo_lock);
191 static inline int osc_object_is_locked(struct osc_object *obj)
193 return spin_is_locked(&obj->oo_lock);
197 * Lock "micro-states" for osc layer.
199 enum osc_lock_state {
210 * osc-private state of cl_lock.
212 * Interaction with DLM.
214 * CLIO enqueues all DLM locks through ptlrpcd (that is, in "async" mode).
216 * Once receive upcall is invoked, osc_lock remembers a handle of DLM lock in
217 * osc_lock::ols_handle and a pointer to that lock in osc_lock::ols_lock.
219 * This pointer is protected through a reference, acquired by
220 * osc_lock_upcall0(). Also, an additional reference is acquired by
221 * ldlm_lock_addref() call protecting the lock from cancellation, until
222 * osc_lock_unuse() releases it.
224 * Below is a description of how lock references are acquired and released
227 * - When new lock is created and enqueued to the server (ldlm_cli_enqueue())
228 * - ldlm_lock_create()
229 * - ldlm_lock_new(): initializes a lock with 2 references. One for
230 * the caller (released when reply from the server is received, or on
231 * error), and another for the hash table.
232 * - ldlm_lock_addref_internal(): protects the lock from cancellation.
234 * - When reply is received from the server (osc_enqueue_interpret())
235 * - ldlm_cli_enqueue_fini()
236 * - LDLM_LOCK_PUT(): releases caller reference acquired by
239 * ldlm_lock_decref(): error case: matches ldlm_cli_enqueue().
240 * - ldlm_lock_decref(): for async locks, matches ldlm_cli_enqueue().
242 * - When lock is being cancelled (ldlm_lock_cancel())
243 * - ldlm_lock_destroy()
244 * - LDLM_LOCK_PUT(): releases hash-table reference acquired by
247 * osc_lock is detached from ldlm_lock by osc_lock_detach() that is called
248 * either when lock is cancelled (osc_lock_blocking()), or when locks is
249 * deleted without cancellation (e.g., from cl_locks_prune()). In the latter
250 * case ldlm lock remains in memory, and can be re-attached to osc_lock in the
254 struct cl_lock_slice ols_cl;
255 /** underlying DLM lock */
256 struct ldlm_lock *ols_lock;
257 /** lock value block */
258 struct ost_lvb ols_lvb;
259 /** DLM flags with which osc_lock::ols_lock was enqueued */
261 /** osc_lock::ols_lock handle */
262 struct lustre_handle ols_handle;
263 struct ldlm_enqueue_info ols_einfo;
264 enum osc_lock_state ols_state;
267 * How many pages are using this lock for io, currently only used by
268 * read-ahead. If non-zero, the underlying dlm lock won't be cancelled
269 * during recovery to avoid deadlock. see bz16774.
271 * \see osc_page::ops_lock
272 * \see osc_page_addref_lock(), osc_page_putref_lock()
274 cfs_atomic_t ols_pageref;
277 * true, if ldlm_lock_addref() was called against
278 * osc_lock::ols_lock. This is used for sanity checking.
280 * \see osc_lock::ols_has_ref
282 unsigned ols_hold :1,
284 * this is much like osc_lock::ols_hold, except that this bit is
285 * cleared _after_ reference in released in osc_lock_unuse(). This
286 * fine distinction is needed because:
288 * - if ldlm lock still has a reference, osc_ast_data_get() needs
289 * to return associated cl_lock (so that a flag is needed that is
290 * cleared after ldlm_lock_decref() returned), and
292 * - ldlm_lock_decref() can invoke blocking ast (for a
293 * LDLM_FL_CBPENDING lock), and osc_lock functions like
294 * osc_lock_cancel() called from there need to know whether to
295 * release lock reference (so that a flag is needed that is
296 * cleared before ldlm_lock_decref() is called).
300 * inherit the lockless attribute from top level cl_io.
301 * If true, osc_lock_enqueue is able to tolerate the -EUSERS error.
305 * set by osc_lock_use() to wait until blocking AST enters into
306 * osc_ldlm_blocking_ast0(), so that cl_lock mutex can be used for
307 * further synchronization.
311 * If the data of this lock has been flushed to server side.
315 * if set, the osc_lock is a glimpse lock. For glimpse locks, we treat
316 * the EVAVAIL error as torerable, this will make upper logic happy
317 * to wait all glimpse locks to each OSTs to be completed.
318 * Glimpse lock converts to normal lock if the server lock is
320 * Glimpse lock should be destroyed immediately after use.
324 * For async glimpse lock.
328 * IO that owns this lock. This field is used for a dead-lock
329 * avoidance by osc_lock_enqueue_wait().
331 * XXX: unfortunately, the owner of a osc_lock is not unique,
332 * the lock may have multiple users, if the lock is granted and
335 struct osc_io *ols_owner;
340 * Page state private for osc layer.
343 struct cl_page_slice ops_cl;
345 * Page queues used by osc to detect when RPC can be formed.
347 struct osc_async_page ops_oap;
349 * An offset within page from which next transfer starts. This is used
350 * by cl_page_clip() to submit partial page transfers.
354 * An offset within page at which next transfer ends.
356 * \see osc_page::ops_from.
360 * Boolean, true iff page is under transfer. Used for sanity checking.
362 unsigned ops_transfer_pinned:1,
364 * True for a `temporary page' created by read-ahead code, probably
365 * outside of any DLM lock.
373 * Set if the page must be transferred with OBD_BRW_SRVLOCK.
377 * lru page list. See osc_lru_{del|use}() in osc_page.c for usage.
381 * Linkage into a per-osc_object list of pages in flight. For
384 cfs_list_t ops_inflight;
386 * Thread that submitted this page for transfer. For debugging.
388 struct task_struct *ops_submitter;
390 * Submit time - the time when the page is starting RPC. For debugging.
392 cfs_time_t ops_submit_time;
395 * A lock of which we hold a reference covers this page. Only used by
396 * read-ahead: for a readahead page, we hold it's covering lock to
397 * prevent it from being canceled during recovery.
399 * \see osc_lock::ols_pageref
400 * \see osc_page_addref_lock(), osc_page_putref_lock().
402 struct cl_lock *ops_lock;
405 extern struct kmem_cache *osc_lock_kmem;
406 extern struct kmem_cache *osc_object_kmem;
407 extern struct kmem_cache *osc_thread_kmem;
408 extern struct kmem_cache *osc_session_kmem;
409 extern struct kmem_cache *osc_req_kmem;
410 extern struct kmem_cache *osc_extent_kmem;
412 extern struct lu_device_type osc_device_type;
413 extern struct lu_context_key osc_key;
414 extern struct lu_context_key osc_session_key;
416 #define OSC_FLAGS (ASYNC_URGENT|ASYNC_READY)
418 int osc_lock_init(const struct lu_env *env,
419 struct cl_object *obj, struct cl_lock *lock,
420 const struct cl_io *io);
421 int osc_io_init (const struct lu_env *env,
422 struct cl_object *obj, struct cl_io *io);
423 int osc_req_init (const struct lu_env *env, struct cl_device *dev,
425 struct lu_object *osc_object_alloc(const struct lu_env *env,
426 const struct lu_object_header *hdr,
427 struct lu_device *dev);
428 int osc_page_init(const struct lu_env *env, struct cl_object *obj,
429 struct cl_page *page, struct page *vmpage);
431 void osc_index2policy (ldlm_policy_data_t *policy, const struct cl_object *obj,
432 pgoff_t start, pgoff_t end);
433 int osc_lvb_print (const struct lu_env *env, void *cookie,
434 lu_printer_t p, const struct ost_lvb *lvb);
436 void osc_lru_add_batch(struct client_obd *cli, cfs_list_t *list);
437 void osc_page_submit(const struct lu_env *env, struct osc_page *opg,
438 enum cl_req_type crt, int brw_flags);
439 int osc_cancel_async_page(const struct lu_env *env, struct osc_page *ops);
440 int osc_set_async_flags(struct osc_object *obj, struct osc_page *opg,
441 obd_flag async_flags);
442 int osc_prep_async_page(struct osc_object *osc, struct osc_page *ops,
443 struct page *page, loff_t offset);
444 int osc_queue_async_io(const struct lu_env *env, struct cl_io *io,
445 struct osc_page *ops);
446 int osc_teardown_async_page(const struct lu_env *env, struct osc_object *obj,
447 struct osc_page *ops);
448 int osc_flush_async_page(const struct lu_env *env, struct cl_io *io,
449 struct osc_page *ops);
450 int osc_queue_sync_pages(const struct lu_env *env, struct osc_object *obj,
451 cfs_list_t *list, int cmd, int brw_flags);
452 int osc_cache_truncate_start(const struct lu_env *env, struct osc_io *oio,
453 struct osc_object *obj, __u64 size);
454 void osc_cache_truncate_end(const struct lu_env *env, struct osc_io *oio,
455 struct osc_object *obj);
456 int osc_cache_writeback_range(const struct lu_env *env, struct osc_object *obj,
457 pgoff_t start, pgoff_t end, int hp, int discard);
458 int osc_cache_wait_range(const struct lu_env *env, struct osc_object *obj,
459 pgoff_t start, pgoff_t end);
460 void osc_io_unplug(const struct lu_env *env, struct client_obd *cli,
461 struct osc_object *osc, pdl_policy_t pol);
462 int lru_queue_work(const struct lu_env *env, void *data);
464 void osc_object_set_contended (struct osc_object *obj);
465 void osc_object_clear_contended(struct osc_object *obj);
466 int osc_object_is_contended (struct osc_object *obj);
468 int osc_lock_is_lockless (const struct osc_lock *olck);
470 /*****************************************************************************
476 static inline struct osc_thread_info *osc_env_info(const struct lu_env *env)
478 struct osc_thread_info *info;
480 info = lu_context_key_get(&env->le_ctx, &osc_key);
481 LASSERT(info != NULL);
485 static inline struct osc_session *osc_env_session(const struct lu_env *env)
487 struct osc_session *ses;
489 ses = lu_context_key_get(env->le_ses, &osc_session_key);
490 LASSERT(ses != NULL);
494 static inline struct osc_io *osc_env_io(const struct lu_env *env)
496 return &osc_env_session(env)->os_io;
499 static inline int osc_is_object(const struct lu_object *obj)
501 return obj->lo_dev->ld_type == &osc_device_type;
504 static inline struct osc_device *lu2osc_dev(const struct lu_device *d)
506 LINVRNT(d->ld_type == &osc_device_type);
507 return container_of0(d, struct osc_device, od_cl.cd_lu_dev);
510 static inline struct obd_export *osc_export(const struct osc_object *obj)
512 return lu2osc_dev(obj->oo_cl.co_lu.lo_dev)->od_exp;
515 static inline struct client_obd *osc_cli(const struct osc_object *obj)
517 return &osc_export(obj)->exp_obd->u.cli;
520 static inline struct osc_object *cl2osc(const struct cl_object *obj)
522 LINVRNT(osc_is_object(&obj->co_lu));
523 return container_of0(obj, struct osc_object, oo_cl);
526 static inline struct cl_object *osc2cl(const struct osc_object *obj)
528 return (struct cl_object *)&obj->oo_cl;
531 static inline ldlm_mode_t osc_cl_lock2ldlm(enum cl_lock_mode mode)
533 LASSERT(mode == CLM_READ || mode == CLM_WRITE || mode == CLM_GROUP);
534 if (mode == CLM_READ)
536 else if (mode == CLM_WRITE)
542 static inline enum cl_lock_mode osc_ldlm2cl_lock(ldlm_mode_t mode)
544 LASSERT(mode == LCK_PR || mode == LCK_PW || mode == LCK_GROUP);
547 else if (mode == LCK_PW)
553 static inline struct osc_page *cl2osc_page(const struct cl_page_slice *slice)
555 LINVRNT(osc_is_object(&slice->cpl_obj->co_lu));
556 return container_of0(slice, struct osc_page, ops_cl);
559 static inline struct osc_page *oap2osc(struct osc_async_page *oap)
561 return container_of0(oap, struct osc_page, ops_oap);
564 static inline struct cl_page *oap2cl_page(struct osc_async_page *oap)
566 return oap2osc(oap)->ops_cl.cpl_page;
569 static inline struct osc_page *oap2osc_page(struct osc_async_page *oap)
571 return (struct osc_page *)container_of(oap, struct osc_page, ops_oap);
574 static inline struct osc_lock *cl2osc_lock(const struct cl_lock_slice *slice)
576 LINVRNT(osc_is_object(&slice->cls_obj->co_lu));
577 return container_of0(slice, struct osc_lock, ols_cl);
580 static inline struct osc_lock *osc_lock_at(const struct cl_lock *lock)
582 return cl2osc_lock(cl_lock_at(lock, &osc_device_type));
585 static inline int osc_io_srvlock(struct osc_io *oio)
587 return (oio->oi_lockless && !oio->oi_cl.cis_io->ci_no_srvlock);
590 enum osc_extent_state {
591 OES_INV = 0, /** extent is just initialized or destroyed */
592 OES_ACTIVE = 1, /** process is using this extent */
593 OES_CACHE = 2, /** extent is ready for IO */
594 OES_LOCKING = 3, /** locking page to prepare IO */
595 OES_LOCK_DONE = 4, /** locking finished, ready to send */
596 OES_RPC = 5, /** in RPC */
597 OES_TRUNC = 6, /** being truncated */
602 * osc_extent data to manage dirty pages.
603 * osc_extent has the following attributes:
604 * 1. all pages in the same must be in one RPC in write back;
605 * 2. # of pages must be less than max_pages_per_rpc - implied by 1;
606 * 3. must be covered by only 1 osc_lock;
607 * 4. exclusive. It's impossible to have overlapped osc_extent.
609 * The lifetime of an extent is from when the 1st page is dirtied to when
610 * all pages inside it are written out.
614 * page lock -> client_obd_list_lock -> object lock(osc_object::oo_lock)
617 /** red-black tree node */
618 struct rb_node oe_node;
619 /** osc_object of this extent */
620 struct osc_object *oe_obj;
621 /** refcount, removed from red-black tree if reaches zero. */
622 cfs_atomic_t oe_refc;
623 /** busy if non-zero */
624 cfs_atomic_t oe_users;
625 /** link list of osc_object's oo_{hp|urgent|locking}_exts. */
627 /** state of this extent */
628 unsigned int oe_state;
629 /** flags for this extent. */
630 unsigned int oe_intree:1,
631 /** 0 is write, 1 is read */
635 /** an ACTIVE extent is going to be truncated, so when this extent
636 * is released, it will turn into TRUNC state instead of CACHE. */
638 /** this extent should be written asap and someone may wait for the
639 * write to finish. This bit is usually set along with urgent if
640 * the extent was CACHE state.
641 * fsync_wait extent can't be merged because new extent region may
642 * exceed fsync range. */
644 /** covering lock is being canceled */
646 /** this extent should be written back asap. set if one of pages is
647 * called by page WB daemon, or sync write or reading requests. */
649 /** how many grants allocated for this extent.
650 * Grant allocated for this extent. There is no grant allocated
651 * for reading extents and sync write extents. */
652 unsigned int oe_grants;
653 /** # of dirty pages in this extent */
654 unsigned int oe_nr_pages;
655 /** list of pending oap pages. Pages in this list are NOT sorted. */
657 /** Since an extent has to be written out in atomic, this is used to
658 * remember the next page need to be locked to write this extent out.
659 * Not used right now.
661 struct osc_page *oe_next_page;
662 /** start and end index of this extent, include start and end
663 * themselves. Page offset here is the page index of osc_pages.
664 * oe_start is used as keyword for red-black tree. */
667 /** maximum ending index of this extent, this is limited by
668 * max_pages_per_rpc, lock extent and chunk size. */
670 /** waitqueue - for those who want to be notified if this extent's
671 * state has changed. */
672 wait_queue_head_t oe_waitq;
673 /** lock covering this extent */
674 struct cl_lock *oe_osclock;
675 /** terminator of this extent. Must be true if this extent is in IO. */
676 struct task_struct *oe_owner;
677 /** return value of writeback. If somebody is waiting for this extent,
678 * this value can be known by outside world. */
680 /** max pages per rpc when this extent was created */
681 unsigned int oe_mppr;
684 int osc_extent_finish(const struct lu_env *env, struct osc_extent *ext,
686 int osc_extent_release(const struct lu_env *env, struct osc_extent *ext);
690 #endif /* OSC_CL_INTERNAL_H */